1 /* 2 * Copyright (C) 2012 Red Hat. All rights reserved. 3 * 4 * This file is released under the GPL. 5 */ 6 7 #ifndef DM_CACHE_POLICY_INTERNAL_H 8 #define DM_CACHE_POLICY_INTERNAL_H 9 10 #include "dm-cache-policy.h" 11 12 /*----------------------------------------------------------------*/ 13 14 /* 15 * Little inline functions that simplify calling the policy methods. 16 */ 17 static inline int policy_map(struct dm_cache_policy *p, dm_oblock_t oblock, 18 bool can_block, bool can_migrate, bool discarded_oblock, 19 struct bio *bio, struct policy_result *result) 20 { 21 return p->map(p, oblock, can_block, can_migrate, discarded_oblock, bio, result); 22 } 23 24 static inline int policy_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock) 25 { 26 BUG_ON(!p->lookup); 27 return p->lookup(p, oblock, cblock); 28 } 29 30 static inline void policy_set_dirty(struct dm_cache_policy *p, dm_oblock_t oblock) 31 { 32 if (p->set_dirty) 33 p->set_dirty(p, oblock); 34 } 35 36 static inline void policy_clear_dirty(struct dm_cache_policy *p, dm_oblock_t oblock) 37 { 38 if (p->clear_dirty) 39 p->clear_dirty(p, oblock); 40 } 41 42 static inline int policy_load_mapping(struct dm_cache_policy *p, 43 dm_oblock_t oblock, dm_cblock_t cblock, 44 uint32_t hint, bool hint_valid) 45 { 46 return p->load_mapping(p, oblock, cblock, hint, hint_valid); 47 } 48 49 static inline int policy_walk_mappings(struct dm_cache_policy *p, 50 policy_walk_fn fn, void *context) 51 { 52 return p->walk_mappings ? p->walk_mappings(p, fn, context) : 0; 53 } 54 55 static inline int policy_writeback_work(struct dm_cache_policy *p, 56 dm_oblock_t *oblock, 57 dm_cblock_t *cblock) 58 { 59 return p->writeback_work ? p->writeback_work(p, oblock, cblock) : -ENOENT; 60 } 61 62 static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock) 63 { 64 p->remove_mapping(p, oblock); 65 } 66 67 static inline int policy_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock) 68 { 69 return p->remove_cblock(p, cblock); 70 } 71 72 static inline void policy_force_mapping(struct dm_cache_policy *p, 73 dm_oblock_t current_oblock, dm_oblock_t new_oblock) 74 { 75 return p->force_mapping(p, current_oblock, new_oblock); 76 } 77 78 static inline dm_cblock_t policy_residency(struct dm_cache_policy *p) 79 { 80 return p->residency(p); 81 } 82 83 static inline void policy_tick(struct dm_cache_policy *p) 84 { 85 if (p->tick) 86 return p->tick(p); 87 } 88 89 static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen) 90 { 91 ssize_t sz = 0; 92 if (p->emit_config_values) 93 return p->emit_config_values(p, result, maxlen); 94 95 DMEMIT("0"); 96 return 0; 97 } 98 99 static inline int policy_set_config_value(struct dm_cache_policy *p, 100 const char *key, const char *value) 101 { 102 return p->set_config_value ? p->set_config_value(p, key, value) : -EINVAL; 103 } 104 105 /*----------------------------------------------------------------*/ 106 107 /* 108 * Creates a new cache policy given a policy name, a cache size, an origin size and the block size. 109 */ 110 struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size, 111 sector_t origin_size, sector_t block_size); 112 113 /* 114 * Destroys the policy. This drops references to the policy module as well 115 * as calling it's destroy method. So always use this rather than calling 116 * the policy->destroy method directly. 117 */ 118 void dm_cache_policy_destroy(struct dm_cache_policy *p); 119 120 /* 121 * In case we've forgotten. 122 */ 123 const char *dm_cache_policy_get_name(struct dm_cache_policy *p); 124 125 const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p); 126 127 size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p); 128 129 /*----------------------------------------------------------------*/ 130 131 #endif /* DM_CACHE_POLICY_INTERNAL_H */ 132